Securities - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024
Debt Securities, Available-for-sale [Line Items]
Accrued interest receivable	$ 482	$ 509
Mortgage-backed securities with a book value	210,889	219,523
Fair Value	$ 187,753	190,475
Percentage of equity securities	10.00%
Gross gains from sales of available for sale securities	$ 30	0
Gross losses from sales of available for sale securities	101	0
Tax benefit to net realized gains (losses)	(20)	0
Investments in debt and marketable equity securities	$ 173,405	$ 185,652
Temporarily impaired debt securities percentage of investment securities portfolio	92.00%	97.00%
Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration]	Interest Receivable	Interest Receivable
Asset Pledged as Collateral with Right [Member]
Debt Securities, Available-for-sale [Line Items]
Carrying value of securities pledged as collateral	$ 102,268	$ 118,577
Tax benefit to net realized gains (losses)	20	0
Mortgage-backed securities – GSE residential [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	192,261	192,556
Fair Value	171,079	166,236
Investments in debt and marketable equity securities	158,479	163,470
Small Business Administration [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	14,894	16,387
Fair Value	13,114	14,086
Investments in debt and marketable equity securities	13,114	14,086
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Investments in debt and marketable equity securities	$ 173,405	$ 185,652

Debt securities greater than stated percentage of equity securities.

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Temporarily impaired debt securities percentage of investment securities portfolio.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, after allowance for credit loss, of accrued interest on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Indicates line item in statement of financial position that includes accrued interest, after allowance for credit loss, on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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